Just a Little Advice Needed

My mama is 75 and her PCP has officially diagnosed her with dementia-close family members knew this for a while now but she is really hard-headed and she has to make the decision as to the doctors she wants to see. We are waiting on them to make her an appointment with a neurologist. I feel like smudge. I am calling to check on her a few times a week, but would make excuses to go visit because she is so ''mean''. She don't like anybody or anything. She has always been hard to handle and i just blamed the attitude on her getting older. I never associated the attitude with dementia. She and my stepdad still live independently. But he has a condition that doctors still have not been able to diagnose. He has strength in his legs but it's like his brain won't tell his legs to move so he has to use a walker. He falls a lot now and we have to call the lift team because he don't have the strength to get himself off of the floor. He should be in a skilled facility nursing home. Mama is taking care of him as best that she can and this has put a lot of stress on her. His brain is still sharp for his age=almost 80. Here's my issue: as he still has a sound mind, he refuses to leave home. We can't make him leave his home. Just wondering if anyone has gone through this that they may have a suggestion. Mama would happily leave and go to assisted living just to get away from being a caretaker, but he cannot stay by himself. And what happens if she wanders off-he can't just up and run after her. Any takers on this subject would be greatly appreciated.